The second study evaluated 20-year follow-up data from 1,851 women with invasive breast cancer randomized to treatment with total mastectomy, lumpectomy alone, or lumpectomy and breast irradiation.

• 第二项研究则评估1,851位侵袭性乳腺癌，并随机接受全乳房切除术，乳腺肿瘤切除术或乳腺肿瘤切除术加放射治疗的女性20年的随访资料。